/*******************************************************************************
 *     ___                  _   ____  ____
 *    / _ \ _   _  ___  ___| |_|  _ \| __ )
 *   | | | | | | |/ _ \/ __| __| | | |  _ \
 *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
 *    \__\_\\__,_|\___||___/\__|____/|____/
 *
 *  Copyright (c) 2014-2019 Appsicle
 *  Copyright (c) 2019-2024 QuestDB
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

package io.questdb.test.griffin;

import io.questdb.griffin.ExpressionParserListener;
import io.questdb.griffin.model.ExpressionNode;
import io.questdb.std.str.StringSink;

public class RpnBuilder implements ExpressionParserListener {
    private final StringSink sink = new StringSink();

    @Override
    public void onNode(ExpressionNode node) {
        if (node.queryModel != null) {
            sink.put('(').put(node.queryModel).put(')').put(' ');
        } else {
            sink.put(node.token).put(' ');
        }
    }

    public void reset() {
        sink.clear();
    }

    public final CharSequence rpn() {
        if (sink.charAt(sink.length() - 1) == ' ') {
            sink.clear(sink.length() - 1);
        }
        return sink;
    }
}
